Physical Explanation of Magnetic and Magnetocaloric Effects of La0.7Sr0.3Mn0.95Ni0.05O3 in Different Synthesis Methods

The magnetocaloric effect properties for potential applications of magnetic refrigerator technology: a review

“…Moreover, mismatch effect plays a role in controlling the type of magnetic phase transition and T C values. 1,17,18,164 Yuan et al revealed a correlation between the mismatch effect values and 〈 r A 〉, producing a pattern similar to the T C pattern in the cases of compounds X, Y, and Z. 165 This correlation is depicted in Fig.…”

“…Other parameters related to magnetic properties such as T C , −Δ S M , and magnetic phase transition are the mismatch effect ( σ 2 ). 1 In perovskite manganite (PM) materials, a large value of σ 2 is defined as the difference in the ion radius values for each ion at site-A compared to 〈 r A 〉, and it can be formulated as follows: 8,162–164 σ 2 = Σ x i r i 2 − 〈 r A 〉 2 where, 〈 r A 〉 is the average ion radii size, x i is the ion content in the system, and r i is the ion radii size in the system. For example, Razaq et al calculated the σ 2 values for La 0.8 K x Ba 0.05 Sr 0.15− x MnO 3 ( x = 0.00–0.20) with results from 3.833 × 10 −3 to 18.101 × 10 −3 .…”

“…17 Additionally, Bangrong He et al reported La 0.8− x Gd x Sr 0.2 MnO 3 ( x = 0.00–0.10) with σ 2 values from 1.024 × 10 −3 to 7.594 × 10 −3 . 164 Both studies reported changes in their physical and magnetic properties which are connected to local lattice distortion with a random placement of oxygen. Moreover, mismatch effect plays a role in controlling the type of magnetic phase transition and T C values.…”

“…The choice of production method plays a crucial role in investigating MCE properties as it is highly sensitive to the material's characteristics. Some of the methods used by researchers consist of solid-state reaction (SSR), 167–171 sol–gel (SG), 16,17,164 polyol (P), solvothermal (ST), 24 ball milling (BM) or high energy ball milling (HEBM), 116,117,172 pore-wetting (PW), 23 wet-mixing (WM), 16 hydrothermal (HT) methods, 1 etc. It is known that each method has its own targeted advantages.…”

“…Many researchers use the SG method due to its advantages such as the manufacturing process, short experimental cycles, production of more homogenous particle sizes, adjustable sintering temperatures, and shorter sintering treatment times compared to SSR and BM methods. 16,164 However, materials produced using the SG method tend to have lower crystallinity than those produced using the SSR method. 1 Some materials produced using the SG method include La 0.7 Ca 0.1 Sr 0.1 Ba 0.1 MnO 3 , 16 La 0.8− x K x Ba 0.05 Sr 0.15 MnO 3 , 17 and La 0.7 Gd x Sr 0.3− x MnO 3 .…”